Real-time Simulation Of Power Electronic Circuits Based On FPGA

With the development of high frequency of power electronics technology,and real-time simulation because of its fast simulation,high precision is becoming the the primary choices of current high-frequency power electronic system simulation.The traditional power electronic system simulation tools are generally a multi-PC or DSP distribution real-time simulation platform,limited to the computing process serialization characteristics of the simulation platform,the typical simulation step size can only reach the order of microseconds,which obviously can not meet the speed requirements of the current high-frequency power electronic system real-time simulation.But the FPGA-based real-time simulation platform has a high degree of parallel processing capabilities,which is more suitable for real-time simulation of high-frequency power electronics.Therefore,this paper carried out the study on real-time simulation of high-frequency power electronic circuit based on FPGA.The main work of this paper is as follows:This paper discusses the real-time simulation modeling methods of power electronic circuit based on FPGA.On the basis of various switching device modeling methods and circuit calculation models,this paper chooses the switch function method to model the device.In traditional switching function method,the IGBT module was completely idealized;the conduction voltage and on-resistance of device was not considered;IGBT and diode were not respectively studied;at the same time,there are some shortages in the calculation of the loss.So in this paper,improvements are made on the basis of the traditional switching function to enhance the practicality of the device model.The state equation method is used to solve the circuit.By analyzing the working principle of the typical power electronic circuits,and theirs state equation models are established.The discretization of simulation model is completed through numerical integration.With increase of the switching frequency,switching device loss problem has become particularly prominent,especially the switching losses.In this paper,the focuse is on how to calculate the real-time loss of devices in the operation of power electronic circuits.The advantages and disadvantages of various switching loss modeling methods and their applicability are analyzed.Aiming at the high-speed requirement of real-time simulation,this paper uses curve fitting method to approximately calculate the real-time switching loss generated by the IGBT power module during the operation of the power electronic circuit.Based on the method described in this paper,a voltage-based bridge inverter circuit is taken as an example.The program is designed in Verilog language in Quartus II and its experimental environment based on a single FPGA is built.In its simulation model FPGAprograming,the principle of 64-bit floating point addition and multiplication are introduced,and the designs of the operators are completed.The structural and timing design of the FPGA program are also completed.Finally,the results of the model run on the FPGA hardware platform are compared with the simulation results in Plecs.The results verify the feasibility and rationality of the modeling method,circuit solution algorithm and switching loss fitting algorithm to achieve real-time simulation on a single chip FPGA.